An analytical framework for flood water conservation considering forecast uncertainty and acceptable risk

Abstract

This paper addresses how much flood water can be conserved for use after the flood season through the operation of reservoir by taking into account the residual flood control capacity (the difference between flood conveyance capacity and the expected inflow in a lead time). A two-stage model for dynamic control of the flood-limited water level (the maximum allowed water level during the flood season, DC-FLWL) is established considering forecast uncertainty and acceptable flood risk. It is found that DC-FLWL is applicable when the reservoir inflow ranges from small to medium levels of the historical records, while both forecast uncertainty and acceptable risk in the downstream affect the feasible space of DC-FLWL. As forecast uncertainty increases (under a given risk level) or as acceptable risk level decreases (under a given forecast uncertainty level), the minimum required safety margin for flood control increases, and the chance for DC-FLWL decreases. The derived hedging rules from the modeling framework illustrate either the dominant role of water conservation or flood control or the trade-off between the two objectives under different levels of forecast uncertainty and acceptable risk. These rules may provide useful guidelines for conserving water from flood, especially in the area with heavy water stress. The analysis is illustrated via a case study with a real-world reservoir in northeastern China.

Peak Operation Problem Solving for Hydropower Reservoirs by Elite-Guide Sine Cosine Algorithm with Gaussian Local Search and Random Mutation

“…Compared with the above energies, hydropower is seen as one of the most important environment-friendly and pollution-free energy sources since it has the advantages of low operating cost and multiple comprehensive benefits (like flood control, power generation, water supply, shipping and irrigation) [8][9][10]. Meanwhile, the working conditions of hydropower plants can rapidly change in a very short period of time [11][12][13].…”

Multiobjective hedging rules for flood water conservation

“…Studies have conducted hedging analysis for reservoir operations for flood control [ Zhao et al ., ] and for flood water conservation [ Ding et al ., ]. Zhao et al .…”

“…Ding et al . [] followed Zhao et al . [] and extended the hedging analysis to account two objectives—the conservation benefits in the current stage and flood risk in a later stage and provided an analytical framework for flood water conservation.…”

“…Specifically, we address the following twofold question: for a given preference, what is the maximum allowed forecast uncertainty for flood water conservation; for a given forecast level, what is the appropriate range of the preferences to water conservation? The present study extends our previous work [ Ding et al ., ] by incorporating reservoir managers' or stakeholders' preference for water conservation into the analysis conjunctively with other factors such as the levels of forecast uncertainty, the expected inflow, and acceptable flood risk. This extension will allow exploring various hydrological, technological (with forecast technologies) and human behavior conditions for reservoir operation decision making considering conflicting flood control and water conservation objectives.…”

Risk Analysis of Reservoir Flood Routing Calculation Based on Inflow Forecast Uncertainty

“…This complexity inevitably leads to uncertainties or risks in decision-making. Thus, risk analysis in both flood routing and scheduling has been one of the hot topics in the operation and management of reservoirs for a long time [14][15][16]. The uncertainty of flood routing is one of the main sources of forthcoming risk.…”